Pipe connection



Sept. 12, 1950 J.C.mCHARDSON PIPE CONNECTION Filed Jan. 18, 1947vHVVENTUR. v James C. Ff'oarzm/z BY www @MLM MWL ATToR/s/m/.Y

Patented Sept. 12, 1950 rire coNNEc'rioN James C. Richardson, Waterbury,Conn., assigner to The Brockway `Company, Naugatuck, Conn., acorporation of Connecticut Application January 18, 1947, Serial No.722,771

2 Claims. (Cl. 285-86) This invention relates to coupling or connectingmeans for threadless pipe, tubing, conduitand the like, particularly forVconnecting the same to other or similar structures, and to form `aleaktight connection therewith.

In my co-pending applications, Serial Nos. 702,026, filed October 8,1946 and 716,370, filed December 14, 1946, I have disclosed connectingmeans for ductile or bendable threadless pipe, wherein a ductile pipelwall is upset to form a flange of double-walled thickness, extending,in radial direction therefromsaid ange cooperating with coupling membersbetween which lit is clamped to form a leaktight connectiontherewith.The term pipe is used herein to mean any form of hollow elongatestructure ordinarily called pipes, tubes, tubing or conduit. Y

This invention relates to a modification of the couplings described inmy aforesaid co-pending applications, especially adapted for ductilepipewhen the character of the material of which the pipe is made makes theformation of a .perma-y nently tight joint between the coupling membersn placed at the end of the pipe so that by making.

the bore of the opposite coupling member to whichthe pipe is connectedthe same as the internal diameter of the pipe, a passage` of uniformdiameter was formed through the coupling. ,In.

other constructions, however, in which the upset flange was formed ashort distance from the end of the pipe with an end portion of the pipeprojecting therefrom,

ber, so that the passage through the coupling was varied at least by thethickness of the walls of` The extending end portion of .theA

the pipe. pipe Ventering the bore ofy a coupling member is ordinarilyreceived therein with a sliding t so that engagement of the end of thepipe with the walls of the bore afforded no substantial support` againstminor displacement or vibration of the pipe in lateral direction withinthe coupling.

In cases in which the pipe wall is relatively.

thin and consequently frangible, or when the walls of the flange are ofrelatively ductile material, such as soft copper, so that the pipeenclosed by the coupling is relatively susceptible v to excessivedeformation upon application of ex;- ternalforces or vibration, it isdesirable to provide additional support for the walls of the pipe theprojecting pipe fend. entered the bore of the opposite coupling memfl ata point spaced from the clamped flange. A` similar situation arises whenthe pipe is of exli-V ceptionally rigid material, so that the pipe wallcan cooperate with a surrounding wall or bore to increase the rigidityof the coupling; or in cases Where the formation of a leaktight jointwith the upset flange is rendered diificult by: the rigidity of thematerial of the flange.

In accordance with this invention, the end portion of the pipe extendingbeyond the flange is, not merely enclosed in the bore of the coupling;member receiving the same as'by a sliding fit, but is compressed againstthe wall of the bore in said' coupling member, providing added supportto prevent deformation or displacement of the pipe in the coupling andreinforcing the support' provided by the clamped upset flange.

Thus, in accordance with this invention, an; upset double thicknessflange is formed rin a ductile pipe at a point spaced from the end ofthe pipe, and the end portion of the pipe projects into the oppositecoupling member. The boreof the latter is preferably formed so as topro. vide a passage of uniform diameter through the coupling despite thefact that the end portion of the pipe projects into the same, byproviding a counterbore in the coupling member receiving the end vof thepipe, said counterbore terminatingin an abutment against which the endof the pipe is seated,.while the remainder of the bore is of the samediameter as the inside of the pipe.

Moreover, the counterbore is shaped so as tor compress the extending'endportion of the pipe within its Walls, thus forming a rigid support fortheend portion of the .pipe against lateralfdisplacement, and therebyreinforcing the said effect of the flange-engaging surfaces of saidcoupling members when the flange is clamped between them.

Thisis accomplished, in accordance with my invention, by constructingthe counterbore of slightly less length than the extending end portionof the pipe received thereby, so that the latter is. compressedin axialdirection when the couf pling members are forced into clamping engage#ment with the flange. Axial compression of said end portion of the pipetends to expand the same Y pling, while in another form of theinvention, the

abutment can be undercut to form an interlock with the end of the pipe.The latter can be preshaped to iii; said undercut abutment, or deformedto conform therewith when forced axially into engagement with theabutment.

Moreover, if desired, the walls of the counter bore can be taperedinwardly so that the end portion of the pipe, upon entering thecounterbore, are further compressed against the walls of the same by theconstricting effect o-f the tapering on the end portion of the pipe asit enters the counterbore.

By virtue of the compression of the walls of the projecting ends of thepipe against the walls of the counterbore in the coupling member, thepipe is positively supported against lateral displacement, and ifdesired, a leaktight connection can be formed between the projecting endof the pipe and the wall of the counterbore, as well as with theabutment engaging the end of the pipe.

Other features a-nd advantages of the invention will appear from thefollowing description, taken in conjunction with the accompanyingdrawing wherein:

Figure 1 is an axial cross-sectional View of a coupling in accordancewith the invention.

Fig. 2 is a side view, partly in axial cross section, of a modified formof my coupling.

Fig. 3 is a transverse cross-section along the line `3--3 in Fig. 4,showing the coupling 'ef Fig. 1 employed with welded steel tubing of theBundy type.

Fig. 4 is an enlarged detail in axial crosssection along the line 4--4of the coupling of Fig. 3.

Referring to the drawings, the coupling of Fig. 1 comprising a length ofductile pipel IQ, for example, a pipe of ductile metal, such as copper,steel, tin, zinc, aluminum or alloys of these'materials, having adjacentan end thereof, a double--v thickness flange or upset portion II,extending substantially in radial direction therefrom, and an undeformedend portion I2 of the pipe extending out from said iiange.

The upset flange I I can be made, for example, by the method disclosedin my co-pending appli-f cation, Serial No. 702,026, of October 8l 1946,wherein an unconned length of the pipe'ad-f jacent the end thereof, issubjected to axial com-` pression while confining the pipe walls onopposite sides of said unconiined portion against radial expansion.Application of such compression to the unconnned portion of the pipe,causes said portion to expand in the form of anari-f nular ridge orbead, which is'then further compressed until the sides thereof areforced together to yield the double walled flange shoy'fn in thedrawing. In some cases, it is advantageous to support the inner walls ofthe pipe against constriction during formation of said flange, forexample, by insertion of a rigid support Vsuch as a mandrel into thebore of the pipe.

A female coupling member i3, having a rearwardly extending sleeveportion I4 with a bore therein corresponding in diameter to the outsidediameter of the pipe I0, encircles the latter be-v hind the fiange I I.The coupling member I3 has a cavity extending inward from its oppositeor front end, of sufficient diameter to receive the upset ilange Il,said cavity terminating at a shoulder I5 against which the `flange IIcan be seated. Threads I6 extend inward from the f mouth of the cavityand are adapted to engage a correspondingly threaded coupling ,membensaid threads preferably terminating at an inner cylindrical portion I'Iof said cavity, which extends a short distance inward to join theshoulder The other coupling member I 8 is a male fitting, which can beattached to a structure I9, for example, by a threaded portion 2D at itsrear end. It is advantageously provided with a nut portion 2|, forexample, of hexagonal or square shape, to facilitate its installation onthe structure I9. The coupling member I3 has a bore 22 extendingtherethrough, preferably of the same diameter as the internal diameterof the pipe I0. Extending toward its opposite or front end, the couplingmember I8 has a set of external threads 23 for engaging the threads I6on the coupling member I3. At its front end, the mem berI8 has a surface24 conforming substantially in shape to the front side of the upsetflange II. Preferably it also includes a cylindrical portion 25 betweenthe end surface 24 and external threads 23 for telescopically enteringthe cylindrical portion I'I of the female coupling niember I3.

' Provision of the tclescopical cngageable portions I'I and 25 withmembers I3 and I8 forms,y

together with the shoulder I5 and end surface 24, an annular spaceadapted to confine the uDSet iiange II on the pipe when the two couplingmembers are threaded together. AIn order to prevent the inner edge ofthe shoulder I5 and of end surface 24 from biting into the material ofthe flange II at its base, the corners I5 and 24' thereof can beslightly rounded, i. e. constructed with a curvature of small radius.ydisclosed in my co-pending application, Serial No. 716,370 of December14, 1946 the flange II is compressed within said annular space, and byconfining it therein, excessive deformation of the flange is avoided.Moreover, as disclosed in said application, it is advantageous to formthe shoulder I5 and end surface 24 of the members I 3 and I8 so thatthey diverge slightly from each other in radial direction adjacent theirend peripheries so that when clamped against the flange II, they forcethe material thereof radially outward to substantially fill said annularchamber, and thereby entrap the flange II within said chamber. v

In accordance with the present invention, the coupling member I8 has acounterbore 26, thef diameter of which conforms with the outsidevdiameter of the end portion I2 of the pipe, and which is thus adapted toreceive said end'portion, said counterbore terminating at an abut.' ment2.1 for engaging the end, of the pipe The] abutment 2l is spaced fromthe end Surface .2.4 of the coupling member I8 by a distance slightly'less than the length of the end portion I2 of the pipe. Thus, when theiiange II is clamped` between the shoulder I5 and end surface ,Z4-vofcoupling members I3 and I the end portioni I2 of the pipe is forcedagainst the abutment 21 and thus subjected to axial compression.

In making up the connection with the coupling of Fig. l, the pipe III isinserted with its end portion I 2 extending into the counterbore 2t ofycoupling member I8 until the end olf the bib@` engages the abutment 21at the inner end of the counterbore 26. Coupling member i3 is their.threaded on to member I8 behind the pipe flange II until its shoulder I5engages the rear surface of said flange. Upon further tightening of memeber I3 on member |18, iiange II is clamped firmly j between shoulder I5and end surface 24 of the:

coupling members, and the metal of the flange isA forced tofillthe'annu'larcavity formed by said' surfaces together with thetelescoped cylindrical portions I1 and25 of thetwo-ooupling members. Atthe same time, endporti'on I'Zof the `pipe is subjected tocompression'inaxial direction between the abutment '21 in couplingmember I8 and shoulder 'I 5 of the coupling member I3. Such compressiontends to expand the' end portion I2 of the pipe in radial direction,thus vforcing the walls of said end portion outward against the walls ofthe counterbore 26. Thus, when the connection is fully tightened, a sealis formed not only between the flange `I andl'end surface 24 of couplingmember" I 8; but also between 'abutment 21 and the end of -the pipe, andfurther between the exterior of the en'd'portion vI2 of the pipe and thewalls of thev counterbore .26.

The pipe 'lll' is -firmly"held against lateral and longitudinaldisplacemenuqthe supporting effect of the ange clamped by the couplingmembers being.reinforced by'the compressed engagement of the end portionI2 with the ywalls of counterbore 26. Thus, .the pipe is much morefirmly supported against lateral displacement than in the case of acoupling in which the flange alone is forcibly'clamped between' thelcoupling membersl v' 'A` second` connection embodying` my invention, issho-wn in Fig. 2. This embodiment comprises a female coupling member|3a, similar in all respects to coupling member |3 of'Fig. 1, vthe corresponding parts being identied by the same reference numerals with thepostscript a. Thusjthe coupling member .i3d has a rearwardly extendingsleeve |4a, with a bore conforming to the outside diameter of the pipeto be engaged thereby, a cavity in the opposite end of said memberhaving internal threads I6a, a cylindrically walled portion Ila, and aharige-engaging shoulder ld, shaped to t the rear side of an upsetdouble-walled ange 3| adjacent the end of a length of threadless pipe36. Said length of threadless pipe 33, which has adjacent the endthereof an upset double-wall fiange 3|, also has an end portion 32extending outwardly from the iiange, said end portion being originallyshaped like the end portion I2 of Fig. 1. If desired, how ever, the endportion 32 can be pre-formed with slightly tapered walls, and itsleading end or edge 33 can be made of 11e-entrant conical shape.

The opposite coupling member 34, like member I8 in Fig. l, isadvantageously provided with means such as a threaded portion 35 at itsrear end for fastening it in a correspondingly threaded orifice in astructure 36 to which it is to be secured, and a nut portion 31 forengaging a wrench. The o-pposite or front end of member 34 has externalthreads 38 for engagement with the internal threads |6ct of member 13a,and a short cylindrical portion 39 extending outward Ifrom the threads38 for telescopically entering the cylindrical portion Ila of the cavityof coupling member I3a, while the front end surface 40 of couplingmember 34 is shaped to engage and fit the front side of the ange 3| onpipe 3U. The coupling member 34 also has a bore 4| extendingtherethrough, preferably of the same diameter as the internal diameterof the pipe 3D.

In accordance with the invention, the coupling member 34 has, inaddition, a counterbore 42 entering the same from the front end thereof,said counterbore having gradually inclined walls, tapered inwardly andterminating at an undercut annular abutment 43 for engaging the end 33of the pipe 30, the length of said counterbore being slightly lessthanfth'at of the end portion 32 of the pipe.

In making up the connection of Fig; 2, the end portion 32 of pipe 3|) isinserted into the counterbore 42 `fof coupling member 34 until its endsurface 33 engages the undercut abutment 43 at the inner end of thecounterbore, or until its `end encountersthe tapered walls of thecounterbore 42. Coupling member |3a is then threaded onto couplingmember 34 until its shoulder ld engagesv direction, causing it to expandoutwardlyfand' press against the gradual tapered Wallsv of thecounterbore 42, thus'providing positive support for the end portion ofthe pipe' in addition to support provided bythe clamping' of the flange3| between the fiange-engaging surfaces 15a, and lo ofthe two couplingmembers. The pressure of the end portion 32 against the walls of thecounterbore is further'reinforced by the constricting effect of the'taper on the pipe and if'` the latter is originally larger than theinner end Asinthe coupling of Fig. l,`

of the counterbore. flange 3| is forced outward to ll the annular spacebetween the end surface- 4|) and shoulder Ia, and is confined withinsaid space against excessive expansion.

A leak-tight engagement is thus formed between the end portion of thepipe and the counterbore between the end of the pipe and the abutment,as well as between the clamping surfaces of the coupling members and theupset fiange on the pipe. This arrangement insures a leaktightconnection with steel pipe, as well as a reinforced support for highlyductile pipe, such as copper tubing.

Figs. 3 and 4 show the coupling of Fig. 1 applied to an upset pipe Illbof steel tubing of the Bundy type which is made by wrapping sheet steellongitudinally upon itself, and welding the superposed plies together.As a result, the tubing has a longitudinal seam forming a groove 44along the tubing which often forms a channel for leakage when the tubingis assembled with a coupling.

However, when the pipe lllb having a double walled upset flange IIb andan end portion |211` projecting from the flange, is assembled with thecoupling of Fig. 1, the projecting end portion |2b, when axiallycompressed within the counterbore of coupling member I3 is expandedoutward with great force against the walls 26 of the counterbore,preventing the pipe from turning relative to the member I8, as member I3is tightened thereon. By constructing the walls 26 of the counterbore ofrelatively ductile metal such as brass, the metal thereof is forced intothe groove 44 thus sealing the same against leakage.

The rounded corner 24 at the junction of the counterbore 26 and fiangeengaging surface 24 of coupling member I8 is forced against the surfaceof the pipe Illb with great pressure at the base of flange I Ib, as thecoupling is tightened. Since the pipe is held against turning, the metalof the corner 24' is deformed into the groove 44 forming a secure sealat this point, and preventing any leakage between the pipe and coupling7, member. Construction of surfaces 24: and I5 so that they diverge inradial direction insures adequate pressure at shoulder- 24 to produce'the aforesaid sealingy effect.

Variations can be made in the construction of my invention withoutdeparting from the scopel thereof. Thus, the arrangement of theinterengageable threads whereby the coupling members are broughttogether can be reversed so; that the female: member engagesv the frontinstead of` therear of the upset flange, and includes tl'iecounterlzioreand abutment for engaging, the: end portion of the' pipe, while the malemember has merely a bore: tting'the outside diameter of: the pipe andits ange-engaging surface nts againstthe rear of the flange on pipe.

Other variations and modifications can be made within the scopeof theinvention andportions of the improvements can be used without others.

I claim:

1 A coupling for threadless ductile pipe having an, upsetdoublefth-icknessflangeadjacent an endthereof and' extendingsubstantially in radial direction therefrom, and anendv portion of thepipe extending outward from said flange, said coupling comprising: apair of coupling members, one member having a-.bore for slidablyreceiving the pipe behindl the flange,- asurface facing in axialdirection for clamping against the rear of the fia/nge, and the other ofsaid: members having av surface for clamping against the front of theflange anda counterbore for receiving the outwardly extending endportion of the pipe, and

terminating at an annular abutment for engage ing.-l theend of the pipe,the length ofA saidr couniov terboref being slightly less than;thelength of thef extending end portion of the pipe; andv draft meansfor forcing, said coupling members together to clamp said upset flangebetween said flange-l engaging surfaces, and to compress the end' ofvthe pipe against said abutment, whereby the walls of said# outwardlyvextending portion ofthe pipeA arey expanded outward against the walls ofsaid counterbore.

21. A coupling as defined in claim 1,. wherein the walls of saidcounterbcreare tapered gradu-l ally inwardv toward said abutment, saidvextend'- ing end portion of the pipe being forced against the walls ofsaid tapered portion of the-counter@- bore upon clamping said flange:between said flange-engagingv surfaces in response to operation of saiddraft means.

JAMES C. RICHARDSON'.

REFERENCES CITED The* following references are o'f record in the file ofthis' patent:

STATES PATENTS

